--Started modifying my generator/recognizer/parser to use multiple prepositional phrases (i.e., 'the robot went left of the table then right of the box').  For now just using a single temporal preposition (then) to join multiple prepositional phrases at the end of the sentence.  It seems easy to have my generator produce sentences of up to a certain number of prepositional phrases, but is there a way to extend this to an arbitrary number of prepositional phrases without hardcoding the number into the generator (and thus the parser/recognizer)?